Orthopedic surgical instrument for knee surgery

ABSTRACT

An orthopedic surgical instrument for use in knee surgeries includes an elongated body, a pair of output shafts, and a user control. A first output shaft extends out from a first side of the body along a first output axis substantially perpendicular to a longitudinal axis of the elongated body. A second output shaft also extends out from the first side of the elongated body along a second output axis substantially perpendicular to the longitudinal axis of the elongated body. The user control is coupled to the elongated body near a first end and the first and second output shafts are situated near the second end of the elongated body. Each of the first output shaft and the second output shaft are configured to turn independent of one another in response to operation of the user control. Various joint distractors for use with the orthopedic surgical instrument are also disclosed.

TECHNICAL FIELD

The present disclosure relates generally to surgical instruments, andmore particularly, to surgical instruments for use during knee surgeriessuch as total knee arthroscopy.

BACKGROUND

In some orthopedic surgical procedures, such as total knee arthroscopy,surgical instruments generally known as knee distractors have beendeveloped for orienting a patient's knee joint. For example, in a totalknee replacement procedure, controlling the relative positions of apatient's tibia and femur during surgery allows a surgeon to set theorientation of the knee joint and obtain predetermined anatomic andmechanical axes along which the knee joint will operate after surgery.

In order to control the relative position of a patient's tibia andfemur, a knee distractor may be inserted between the proximal end of thetibia and the distal end of the femur and operated to space the tibiafrom the femur to set the orientation and joint space of the knee joint.Some knee distractors can be operated to independently space lateral andmedial sides of the tibia and femur to obtain a predeterminedorientation of the knee joint.

Some distractors may include sensors or scales to measure the jointforce of the patient's knee joint during the distraction process. Suchdistractors are commonly known as ligament balancers. During operation,a ligament balancer may be used to help balance the surrounding softtissue (i.e., ligaments) of a patient's joint. For example, in a totalknee replacement procedure, ligament balancing may be performed toensure a generally rectangular shaped extension gap and a generallyrectangular shaped flexion gap at a predetermined joint force valuebetween the patient's natural or prosthetic proximal tibia and thepatient's natural or prosthetic distal femur.

To do so, a ligament balancer may be positioned between a patient'stibia and femur, similar to a standard distractor, to measure the medialand lateral joint forces and the medial and/or lateral gap displacementswhen the patient's leg is in extension (i.e., the patient's tibia ispositioned at about 0 degrees relative to the patient's femur) and inflexion (i.e., the patient's tibia is positioned at about 90 degreesrelative to the patient's femur). In either extension or flexion, if themedial and lateral gap displacements are not approximately equal (i.e.,do not form a generally rectangular shaped joint gap) at thepredetermined joint force value, ligament release may be performed toequalize the medial and/or lateral gap displacements. Sometimes use of aknee distractor and a ligament balancer may be difficult for a surgeonor assistant and may require multiple insertion and removal proceduresfor each to be used during a single surgery.

SUMMARY

According to one aspect of the present disclosure, an orthopedicsurgical instrument may include an elongated body, a first output shaft,a second output shaft, and a user control. The elongated body may have afirst end and a second end and may include a handle at the first end.The elongated body may also define a longitudinal axis. The first outputshaft may extend out from a first side of the elongated body along afirst output axis that is substantially perpendicular to thelongitudinal axis of the elongated body. The second output shaft mayextend out from the first side of the elongated body along a secondoutput axis that is substantially perpendicular to the longitudinal axisof the elongated body. The user control may be coupled to the elongatedbody near the first end of the elongated body. The first output shaftand the second output shaft may be situated near the second end of theelongated body and may be configured to turn independent of one anotherin response to operation of the user control.

In some embodiments, the user control may also include a first input anda second input. The first output shaft may be configured to turn inresponse to a user operating the first input and the second output shaftmay be configured to turn in response to a user operating the secondinput. The first input may include a first pulley housed inside theelongated body and rotatable about a first input axis that extendsperpendicular to the longitudinal axis of the elongated body. The secondinput may include a second pulley housed inside the elongated body androtatable about a second input axis. The second input axis may be spacedapart from the first input axis that extends perpendicular to thelongitudinal axis of the elongated body.

In some embodiments, the orthopedic surgical instrument may also includea first belt linkage connecting the first pulley to the first outputshaft and a second belt linkage connecting the second pulley to thesecond output shaft. It is contemplated that, the first pulley may bemovable along the longitudinal axis of the elongated body to tension thefirst belt linkage and the second pulley may be movable along thelongitudinal axis of the elongated body to tension the second beltlinkage. The first input may include a knob coupled to the pulley androtatable about the first input axis.

In some embodiments, the first input may include a knob, an indicatorring, and a gear set. The gear set may be coupled between the knob andthe indicator ring so that the indicator ring turns less than onerevolution in response to the knob being turned one revolution. It iscontemplated that, the first output axis and the second output axis maybe coplanar.

In some embodiments, the first output shaft may includes a proximal endcoupled to the elongated body and a distal end having a driver head withat least one flat surface extending along the first output axis. Thesecond output shaft may include a proximal end coupled to the elongatedbody and a distal end having a driver head with at least one flatsurface extending along the first output axis.

In some embodiments, the elongated body may be formed to include anaccess aperture extending through the elongated body. The accessaperture may be substantially perpendicular to the longitudinal axis ofthe elongated body and may be situated between the user control and thesecond end of the elongated body.

According to another aspect of the present disclosure, an orthopedicsurgical instrument may include a joint distractor and a driver. Thejoint distractor may include a tibial platform, a medial paddle, and alateral paddle. Each paddle may be configured to be raised and loweredrelative to the tibial platform independent of the other paddle. Thedriver may include an elongated body, a user control coupled to theelongated body, a medial output shaft extending out from the elongatedbody and operatively coupleable the medial paddle, and a lateral outputshaft extending out from the elongated body and operatively coupleableto the lateral paddle. The medial output shaft may be configured to movethe medial paddle between a raised position and a lowered positionrelative to the tibial platform in response to operation of the usercontrol. The lateral output shaft may be configured to move the lateralpaddle between a raised position and a lowered position relative to thetibial platform in response to operation of the user control.

In some embodiments, the tibial platform of the joint distractor mayinclude a tibial plate, a medial input, and a lateral input. The medialinput may be configured to engage the medial output shaft when thedriver is coupled to the joint distractor. The lateral input may beconfigured to engage the lateral output shaft when the driver is coupledto the joint distractor.

In some embodiments, the joint distractor may include a medial interfaceblock configured to move between an anterior position when the medialpaddle is in the lowered position and a posterior position when themedial paddle is in the raised position. The medial interface block maybe formed to include a threaded hole extending through the interfaceblock. It is contemplated that the medial paddle may include a rampsurface engaging the medial interface block. The ramp surface of themedial paddle may be a downwardly-facing ramp surface.

In some embodiments, the joint distractor may include a lateralinterface block configured to move between an anterior position when thelateral paddle is in the lowered position and a posterior position whenthe lateral paddle is in the raised position. The lateral paddle mayinclude a ramp surface engaging the lateral interface block.

In some embodiments, the medial paddle may move between an anteriorposition when the medial paddle is in the lowered portion and aposterior position when the medial paddle is in a raised position. Thelateral paddle may move between an anterior position when the lateralpaddle is in the lowered portion and a posterior position when thelateral paddle is in a raised position.

In some embodiments, the joint distractor may include a medial swing armpivotably coupled to the medial paddle and the tibial plate. The jointdistractor may also include a lateral swing arm pivotably coupled to thelateral paddle and the tibial plate.

According to another aspect of the present disclosure, an orthopedicsurgical instrument may include a joint distractor and a driver. Thejoint distractor may include a tibial platform, a medial paddle, and alateral paddle. The driver may be operatively coupleable to the jointdistractor and may include a user control situated at a first end and anoutput shaft situated at a second end. The tibial platform may include amedial input configured to be engaged by the output shaft of the driverand a lateral input configured to be engaged by the output shaft of thedriver. Each paddle may be configured to move along an arcuate pathbetween a raised position and a lowered position independent of theother paddle in response to a user coupling the output shaft to one ofthe inputs and operating the user control.

In some embodiments, the joint distractor may include a medial swing armpivotably coupled to the medial paddle and the tibial plate. The jointdistractor may also include a lateral swing arm pivotably coupled to thelateral paddle and the tibial plate.

The tibial platform may include a tibial plate. Each input may includean input screw situated between the tibial plate and one of the medialand lateral paddles.

DESCRIPTION OF THE DRAWINGS

The systems and methods described herein are illustrated by way ofexample and not by way of limitation in the accompanying figures. Forsimplicity and clarity of illustration, elements illustrated in thefigures are not necessarily drawn to scale. For example, the dimensionsof some elements may be exaggerated relative to other elements forclarity. Further, where considered appropriate, reference labels havebeen repeated among the figures to indicate corresponding or analogouselements.

FIG. 1 is a perspective view of a surgical instrumentation systemincluding a joint distractor situated between a patient's tibia andfemur, a driver for adjusting the joint distractor, and a sensor formeasuring tension in a patient's knee ligaments during adjustment of thejoint distractor;

FIG. 2 is a schematic diagram of at least one embodiment of the surgicalinstrument of FIG. 1;

FIG. 3 is a perspective view of the driver of FIG. 1 showing that thedriver includes a pair of user inputs and a pair of output shaftsconfigured to rotate in response to a user rotating the user inputs;

FIG. 4 is a perspective view of the driver of FIG. 3 with a top portionof a housing of the driver removed to show a pair of linkages connectingthe user inputs and the output shafts;

FIG. 5 is a perspective view of the driver of FIG. 4 with the userinputs disassembled showing that each user input includes a knob, anindicator ring, and a pulley;

FIG. 6 is a top view of the driver of FIG. 4 with the knob cut away toshow that the indicator ring is operably connected to the knob by a gearset;

FIG. 7 is a perspective view of the joint distractor of FIG. 1 showingthat the joint distractor includes a tibial platform and a pair ofpaddles configured to be raised and lowered relative to the tibialplatform;

FIG. 8 is an exploded view of the joint distractor of FIG. 7;

FIG. 9 is a perspective view of the joint distractor of FIG. 7 showingthe internal components of the joint distractor when a lateral paddlemoved to a raised position relative to the tibial platform;

FIG. 10 is a perspective view of the joint distractor of FIG. 8 when thelateral paddle is moved to a lowered position relative to the tibialplatform;

FIG. 11 is a perspective view of another joint distractor for use withthe driver of FIGS. 3-6, the joint distractor including a tibialplatform and a pair of paddles configured to be raised and loweredrelative to the tibial platform;

FIG. 12 is a side elevation view of the joint distractor of FIG. 11showing the components of the joint distractor when a lateral paddlemoved to a lowered and anterior position relative to the tibialplatform;

FIG. 13 is a perspective view of the joint distractor of FIG. 12 whenthe lateral paddle is moved to a raised and posterior position relativeto the tibial platform; and

FIG. 14 is a perspective view of an alternative driver for use with thejoint distractors of FIGS. 7-12.

DETAILED DESCRIPTION

While the concepts of the present disclosure are susceptible to variousmodifications and alternative forms, specific exemplary embodimentsthereof have been shown by way of example in the drawings and willherein be described in detail. It should be understood, however, thatthere is no intent to limit the concepts of the present disclosure tothe particular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

References in the specification to “one embodiment”, “an embodiment”,“an example embodiment”, etc., indicate that the embodiment describedmay include a particular feature, structure, or characteristic, butevery embodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to effect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed.

Referring to FIG. 1, a surgical instrumentation system 10 for use duringan orthopedic surgery, in particular a knee surgery, is shown positionedrelative to a patient's knee joint. The surgical instrumentation system10 includes a joint distractor 12, a driver 14, and a force sensormodule 16. The joint distractor 12 is configured to independently spacethe lateral and medial condyles of the patient's femur 3 from theproximal end of the patient's tibia 5. As shown in FIG. 1, the driver 14provides a user interface to an orthopedic surgeon or other healthcareprovider to allow the user to operate the joint distractor 12 while theligaments and patella extending over the anterior face of the patient'sknee joint remain substantially in place. The sensor module 16 includesa plurality of force sensors (not shown) and is configured to measuremedial and lateral joint forces between the patient's femur 3 and tibia5. The sensor module 16 may be used in with the joint distractor 12 anddriver 14 to measure joint forces of the patient's knee joint duringdistraction thereof. In the illustrative embodiment, the sensor module16 is of the type described in U.S. patent application Ser. Nos.12/415,172; 12/415,350; 12/415,365; and 12/415,290, each of which wasfiled on Mar. 31, 2009 and is hereby incorporated by reference herein.However, in other embodiments, other types of sensor modules or otherdevices may be used in conjunction with the distractor 12 and driver 14to measure joint forces of the patient's knee joint. It should beappreciated that the concurrent use of the joint distractor 12, driver14, and sensor module 16 allows a surgeon to simultaneously adjust theorientation of the knee joint and monitor ligament balance.

Referring now to FIG. 2, the joint distractor 12, the driver 14, and thesensor module 16 of the surgical instrumentation system 10 are showndiagrammatically. As suggested by the dashed line connection in FIG. 2,the driver 14 and the sensor module 16 are temporarily coupled orengaged with the joint distractor 12 such that the surgicalinstrumentation system 10 may be assembled during a surgical procedure.For example, one method of assembling the surgical instrumentationsystem 10 during surgery may include the steps of positioning the sensormodule 16 in contact with the proximal end of a patient's tibia,positioning the joint distractor 12 on top of the sensor module 16between a patient's femur 3 and tibia 5 to engage the proximal end ofthe patient's tibia and the distal end of the patient's femur, andcoupling the driver 14 to the joint distractor 12.

The joint distractor 12 includes a tibial platform 20, a pair of paddles22, 24, and a pair of interfaces 26, 28 coupled between the tibialplatform 20 and the paddles 22, 24 as shown in FIG. 2. The tibialplatform 20 is configured to be coupled with the driver 14 to receiveuser inputs during operation of the joint distractor 12 and to seat orrest on a corresponding tibial paddle of the sensor module 16 in thoseembodiments wherein the system 10 includes the sensor module 16. Thepair of paddles 22, 24 include a medial paddle 22 and a lateral paddle24 each configured to be placed in contact with a respective medial orlateral condyle of the patient's femur 3. The interfaces 26, 28 includea medial interface 26 and a lateral interface 28 each of which isconfigured to independently raise and lower a respective medial paddle22 or lateral paddle 24 relative to the tibial platform 20 in responseto a surgeon operating driver 14 as discussed in more detail below. Itshould be appreciated that the joint distractor 12 and driver 14facilitate independent movement of the patient's medial and lateralfemoral condyles relative to the patient's tibia.

The tibial platform 20 includes a tibial plate 30, a medial input 32,and a lateral input 34 as shown diagrammatically in FIG. 2. The tibialplate 30 is configured to be placed in contact with the proximal end ofa patient's tibia and to support the medial and the lateral inputs 32,34. The medial input 32 and the lateral input 34 are configured to becoupled to the driver 14 and to receive inputs from the driver 14 thatcause respective medial and lateral paddles 22, 24 to be raised orlowered relative to the tibial plate 30.

As discussed above, the driver 14 is operably coupleable to thedistractor 12 to control operation of the distractor 12 (e.g., movementof the medial paddle 22 and lateral paddle 24). The driver 14 includes apair of user inputs 36, 38, a pair of output shafts 42, 44, and a pairof linkages 46, 48 as shown diagrammatically in FIG. 2. The pair of userinputs 36, 38 cooperate to provide a user control 39 that includes amedial user input 36 and a lateral user input 38 each configured toindependently receive a user interaction resulting in the raising orlowering of a medial or lateral condyle of a patient's femur relative toa patient's tibia. The pair of output shafts 42, 44 include a medialoutput shaft 42 configured to be coupled to the medial input 32 of thejoint distractor 12 and a lateral output shaft 44 configured to becoupled to the lateral input 34 of the joint distractor 12. The pair oflinkages 46, 48 include a medial linkage 46 and a lateral linkage 48each of which is configured to independently drive a respective medialor lateral output shaft 42, 44 in response to a surgeon operating themedial user input 36 or the lateral user input 38 of the driver 14 suchthat that medial and lateral condyles of a patient's femur can be movedindependently relative to the patient's tibia.

In one illustrative embodiment, as shown in FIG. 3, the driver 14includes an elongated housing 40 having a first end 56 and a second end58 formed by an upper shell 52 and a lower shell 54. The housing 40forms a handle 50 situated at the first end 56 of the housing 40 suchthat a user can hold the driver 14 while operating the joint distractor12. The user inputs 36, 38 are coupled to the housing 40 along thehandle 50 near the first end 56 of the housing 40. The output shafts 42,44 are spaced apart from the use inputs and extend out from the housing40 near the second end 58 of the housing 40. The housing 40 is alsoformed to include an access aperture 60 situated between the user inputs36, 38 near the first end 56 of the housing 40 and the output shafts 42,44 near the second end 58 of the housing 40. The access aperture 60extends through the housing 40 perpendicular to a longitudinal axis 61of the housing 40 and allows the sensor module 16 to extend through thedriver 14 to be coupled to the joint distractor 12 while the jointdistractor 12 is positioned between a patient's femur and tibia.

The medial user input 36 extends out from a top side 53 of the housing40 near the first end 56 of the housing 40 as shown in FIG. 3. Thelateral user input 38 extends out from a bottom side 55 of the housing40 near the first end 56 of the housing 40. The medial output shaft 42and the lateral output shaft 44 extend out from the top side 53 of thehousing 40 near the second end 58 of the housing 40.

During operation of the driver 14, the medial output shaft 42 is rotatedabout an axis 62 extending along the medial output shaft 42 as suggestedby solid arrow 63 in response to a user rotating the medial user input36 about an axis 66 as suggested by solid arrow 67 shown in FIG. 3.Similarly, the lateral output shaft 44 is rotated about an axis 64extending along the medial output shaft 44 as suggested by dashed arrow65 in response to a user rotating the lateral user input 38 about anaxis 68 as suggested by dashed arrow 69 shown in FIG. 3. Thus, a usercan cause rotation of either output shaft 42, 44 independent of rotationof the other output shaft 42, 44.

Referring now to FIG. 4, the driver 14 is shown with the upper shell 52of the housing 40 removed to show the internal components of the driver14. Each of the user inputs 36, 38 are substantially similar and eachincludes a knob 70, an indicator ring 72, and a pulley 74 as shown inFIG. 4. The knob 70 extends outside the housing 40 of the driver 14 andis operable by a user to cause rotation of the pulley 74. The indicatorring 72 is situated outside the housing 40 and is configured to rotatein response to rotation of the knob 70 at a stepped down rate ofrotation in order to indicate the amount of distraction achieved byrotation of the knob 70. The pulley 74 is situated inside of housing 40and is coupled to a respective output shaft 42, 44 by a respectivelinkage 46, 48 so that the pulley 74 and its respective output shaft 42,44 rotate at a 1 to 1 ratio.

Each of the output shafts 42, 44 are substantially similar, and eachincludes a shank 76 and a pulley 78 as shown in FIG. 4. The shank 76extends out of the housing 40 of the driver 14 and is formed to includea head 80 having a hexagonal shape having six flat sides configured tobe received by the medial or lateral inputs 32, 34 of the jointdistractor 12. In other embodiments, the head 80 may have any shapeincluding at least one flat side or another suitable shape that allowsactuation of the medial and lateral inputs 32, 34 of the distractor 12.The pulley 78 is situated inside of housing 40 and is coupled to arespective user input 36, 38 by a respective linkage 46, 48.

The medial linkage 46 illustratively includes a belt 82 and a pair ofguide rollers 84, 86 as shown in FIG. 4. The belt 82 transmits rotationfrom the pulley 74 of the medial user input 36 to the pulley 78 of themedial output shaft 42. The belt 82 is situated inside the housing 40 ofthe driver 14 and is guided by the rollers 84, 86 to extend around theaccess aperture 60 of the housing 40. The lateral linkage 48illustratively includes a belt 92 and a pair of guide rollers 94, 96.The belt 92 transmits rotation from the pulley 74 of the lateral userinput 38 to the pulley 78 of the lateral output shaft 44. The belt 92 issituated inside the housing 40 of the driver 14 and is guided by therollers 94, 96 to extend around the access aperture 60 of the housing 40and around the belt 82 of the medial linkage 46.

In FIG. 5, the knob 70 and the indicator ring 72 of the medial userinput 36 is disassembled from the driver 14 and the knob 70 is cut away.The knob 70 and the indicator ring 72 of the lateral use input 38 aresubstantially similar to the medial user input 36 and the followingdescription is applicable to both. The knob 70 includes a shaft 98, ashell 99, and a retaining plate 101 as shown in FIG. 5. The shaft 98 isconfigured to couple the shell 99 to the pulley 74 so that the pulley 74rotates with the shell 99 and to couple the shell 99 to the indicatorring 72 via a gear set 100 so that the indicator ring 72 rotates inresponse to rotation of the shell 99. The indicator ring 72 rotates toindicate the amount of additional (or reduced) distraction provided bythe distractor 12 to the medial side of a patient's knee.

The gear set 100 is configured transmit rotation from the knob 70 to theindicator ring 72 at a reduced rate and is illustratively a planetarygear set including a central gear 102, a ring gear 104, and a planetarygear 106 as shown in FIG. 5. The central gear 102 is coupled to theshaft 98 for common rotation with the knob 70 and intermeshes with theplanetary gear 106. The ring gear 104 is coupled for common rotationwith the indicator ring 72 and intermeshes with the planetary gear 106.The planetary gear 106 is coupled for to a tension unit 110 supportingthe pulley 74 for rotation relative thereto.

The indicator ring 72 is formed to external indicator notches 103 andinternal teeth 105. The external indicator notches 103 areillustratively spaced around the indicator ring 72 to indicate about 1mm of distraction. It should be appreciated that in other embodiments,the indicator notches 103 could be replaced with numbers, letters, orother indicators. The internal teeth 105 engage with the ring gear 104so that the indicator ring 72 rotates with the ring gear 104. A user can“reset” or “zero” the indicator ring 72 by lifting the indicator ring 72so that the internal teeth 105 are disengaged from the ring gear 104,setting the starting point of the indicator ring 72 by rotating theindicator ring 72 to a reset or zeroed position, and pushing theindicator ring 72 down so that the internal teeth 105 again engage thering gear 104 and the indicator ring 72 rotates with the ring gear 104.Thus a user is able to monitor and precisely control the amount ofadditional (or reduced) distraction provided by the distractor 12 whileoperating the driver 14.

The knob 70 and the indicator ring 72 are cut away in FIG. 6 to show thearrangement of the gear set 100 when assembled. Illustratively, rotationof the knob 70 results in a 1 to 1 ratio of rotation passed to thepulley 74 through the shaft 98. Further, rotation of the knob 70 resultsin rotation of the indicator ring 72 at a ratio of less than 1 to 1 asrotation is passed through the gear set 100.

Each pulley 74 is supported by a tension unit 110 configured to allowmovement of the pulleys 74 along the longitudinal axis 61 of the driver14 to tension the belts 82, 92 as shown in FIG. 6. Each tension unit 110includes a base plate 112, a bracket 114, and a screw 116. The baseplates 112 are coupled to the housing 40 of the driver 14 along thelongitudinal axis 61 of the driver 14. The brackets 114 support thepulleys 74 and are moved along the longitudinal axis 61 of the driver 14as suggested by arrows 118, 120 in response to rotation of the screws116. The screws 116 extend through the base plates 112 and threadablyengage the brackets 114 so that the brackets 114 are moved in responseto rotation of the screws 116.

Turning now to FIGS. 7-10, the joint distractor 12 of the illustrativeembodiment is shown in detail. The joint distractor 12 is configured tospace the medial and lateral condyles of a patient's femur from thepatient's tibia at desired distances to orient the knee joint. Themedial paddle 22 and the lateral paddle 24 of the joint distractor 12are movable independently relative to the to the tibial platform 20 toallow a user to position the medial and lateral condyles of a patient'sfemur at different distances from the proximal end of a patient's tibiaas suggested in FIG. 7 thereby orienting the knee joint to obtain adesirable mechanical and anatomic axis of the knee joint.

The tibial platform 20 of the joint distractor 12 includes a tibialplate 30, a medial input 32, and a lateral input 34 as shown in FIG. 8.In some embodiments, the tibial plate 30 may be formed to include acavity 122 (see FIGS. 9 and 10) along the underside of the tibial plate30 sized to receive the sensor module 16. In the illustrativeembodiment, the medial input 32 is embodied as a medial input screw 32and the lateral input 34 is embodied as a lateral input screw 34. Eachillustrative input screw 32, 34 is configured to mate with the heads 80of the output shafts 42, 44 of the driver 14 and are coupled to thetibial plate 30 to rotate relative to the tibial plate 30.

The tibial plate 30 includes a bottom panel 131, a front panel 133, anda back panel 145 as shown in FIG. 8. The bottom panel 131 is configuredto engage a patient's proximal tibia during surgery. The front panel 133extends up from the bottom panel 131 along an anterior side of thebottom panel 131 and includes holes 137, 139 configured to support inputscrews 32, 34. The back panel 145 extends up from the bottom panel 131along a posterior side of the bottom panel 133 and includes holes 141,143 configured to support input screws 32, 34.

The medial paddle 22 and the lateral paddle 24 of the joint distractor12 are each formed to include an outer surface 130 and a central surface132 as shown in FIG. 8. The outer surfaces 130 of the paddles 22, 24 areconfigured to contact the medial and lateral condyles of a patient'sfemur during surgery. The central surfaces 132 of the paddles 22, 24extend up from the outer portions 130 and are configured to be situatedbetween the medial and lateral condyles of a patient's femur duringsurgery. The central surfaces 132 of the paddles 22, 24 also form adownwardly-facing ramp surface 134 configured to interact with themedial and lateral inputs 32, 34 to raise and lower the paddles 22, 24independently.

In the illustrative embodiment, the medial interface 26 and the lateralinterface 28 are embodied as interface blocks 26, 28 as shown in FIG. 8.Each interface block 26, 28 is formed to include a threaded hole 136 andan upwardly-facing ramp surface 138. The threaded holes 136 of themedial and lateral interface blocks 26, 28 are configured to mate withthe threads of the medial and lateral input screws 32, 34. Theupwardly-facing ramp surfaces 138 of the medial and lateral interfaces26, 28 are configured to mate with, or otherwise contact, thedownwardly-facing ramp surfaces 134 of the medial and lateral paddles22, 24.

In operation, each of the paddles 22, 24 are configured to move betweena raised position and a lowered position as illustrated by the lateralpaddle 24 in FIGS. 8 and 9. For brevity, only operation of the lateralcomponents 24, 28, 34 of the joint distractor 12 are further discussed,however the following description is equally applicable to the lateralcomponents 22, 26, 32 of the joint distractor 12.

When the lateral paddle 24 is in the raised position, the lateral inputscrew 34 has been rotated in a first direction in order to move thelateral interface block 28 along the lateral input screw 34 to aposterior position as shown in FIG. 9. With the lateral interface block28 in the posterior position, the upwardly-facing ramp surface 138 ofthe lateral interface block 28 pushes the downwardly-facing ramp surface134 of the lateral paddle 24 up thereby lifting the lateral paddle 24vertically up from the tibial plate 30 as suggested by arrow 135 in FIG.9.

When the lateral paddle 24 is in the lowered position, the lateral inputscrew 34 has been rotated in a second direction in order to move thelateral interface block 28 along the lateral input screw 34 to ananterior position as shown in FIG. 10. With the lateral interface block28 in the anterior position, the upwardly-facing ramp surface 138 of thelateral interface block 28 slides along the downwardly-facing rampsurface 134 of the lateral paddle 24 thereby allowing the lateral paddle24 to move vertically down toward the tibial plate 30 as suggested inFIG. 10.

Another illustrative joint distractor 12′, which is configured to beused with the driver 14, is shown in FIGS. 11-13. The joint distractor12′ includes a tibial platform 20′, a pair of paddles 22′, 24′, and apair of interfaces 26′, 28′ coupled between the tibial platform 20′ andthe paddles 22′, 24′ as shown in FIG. 11. The tibial platform 20′ isconfigured to be coupled with the driver 14 to receive user inputsduring operation of the joint distractor 12′ and to the sensor module 16to support the sensor module 16 during surgery. The paddles 22′, 24′ areillustratively embodied as a medial paddle 22′ and a lateral paddle 24′,each of which is configured to be placed in contact with a respectivemedial or lateral condyle of the patient's femur. The interfaces 26′,28′ include a medial interface 26′ and a lateral interface 28′, each ofwhich is configured to independently raise and lower a respective medialor lateral paddle 22′, 24′ relative to the tibial platform 20′ inresponse to a surgeon operating driver 14 so that medial and lateralcondyles of a patient's femur can be moved independently relative to thepatient's tibia to orient a patient's knee joint.

The tibial platform 20′ includes a tibial plate 30′, a medial input 32′,and a lateral input 34′ as shown in FIG. 11. The tibial plate 30′ isconfigured to be placed in contact with the proximal end of a patient'stibia or sensor module 16. The medial input 32′ and the lateral input34′ are configured to be coupled to the driver 14 and to receiveinteraction (e.g., the turning of the inputs 32′, 34′) from the driver14 that cause respective medial and lateral paddles 22′, 24′ to beraised or lowered relative to the tibial plate 30′.

The tibial plate 30′ includes a bottom panel 131′ and a front panel 133′as shown in FIG. 11. The bottom panel 131′ is configured to engage apatient's proximal tibia during surgery. The front panel 133′ extends upfrom the bottom panel 131′ along an anterior side of the bottom panel131′ and includes holes 137′, 139′ configured to support input screws32′, 34′.

In the illustrative embodiment, the medial input 32′ is embodied as amedial input screw 32′, and the lateral input 34′ is embodied as alateral input screw 34′. Each illustrative input screw 32′, 34′ isconfigured to mate with the heads 80 of the output shafts 42, 44 and arecoupled to the tibial plate 30′ to rotate relative to the tibial plate30′.

The medial paddle 22′ and the lateral paddle 24′ of the joint distractor12 are each formed to include an outer surface 130′ and a centralsurface 132′ as shown in FIG. 8. The outer surfaces 130′ of the paddles22′, 24′ are configured to contact the medial and lateral condyles of apatient's femur during surgery. The central surfaces 132′ of the paddles22′, 24′ extend up from the outer portions 130′ and are configured to besituated between the medial and lateral condyles of a patient's femurduring surgery. The central surfaces 132′ of the medial paddle 22′ andthe lateral paddle 24′ of the joint distractor 12′ are coupled to tibialplate 30′ by a pair of swing arms 31′, 33′. The swing arms 31′, 33′guide movement of the paddles 22′, 24′ so that the paddles 22′, 24′ movealong an arcuate path when raised and lowered relative to the tibialplate 30′. The central portions 132′ of the paddles 22′, 24′ also form adownwardly-facing ramp surface 134′ configured to interact with themedial and lateral inputs 32′, 34′ to raise and lower the paddles 22′,24′ independently.

In the illustrative embodiment, the medial interface 26′ and the lateralinterface 28′ are interface blocks 26′, 28′ as shown in FIG. 11. Eachinterface block 26′, 28′ is formed to include a threaded hole 136′ andan upwardly-facing ramp surface 138′. The threaded holes 136′ of themedial and lateral interface blocks 26′, 28′ are configured to mate withthe threads of the medial and lateral input screws 32′, 34′. Theupwardly-facing ramp surfaces 138′ of the medial and lateral interfaces26′, 28′ are configured to mate with the downwardly-facing ramp surfaces134′ of the medial and lateral paddles 22′, 24′.

In operation, each of the paddles 22′, 24′ is configured to move betweena raised position and a lowered position as illustrated by the lateralpaddle 24′ in FIGS. 12-13. For brevity, only operation of the lateralcomponents 24′, 28′, 34′ of the joint distractor 12′ are furtherdiscussed, however the following description is equally applicable tothe lateral components 22′, 26′, 32′ of the joint distractor 12′.

When the lateral paddle 24′ is in the lowered position, the lateralinput screw 34′ is rotated in a first direction in order to move thelateral interface block 28′ along the lateral input screw 34′ to aposterior position as shown in FIG. 12. With the lateral interface block28′ in the posterior position, the upwardly-facing ramp surface 138′ ofthe lateral interface block 28′ slides along the downwardly-facing rampsurface 134′ of the lateral paddle 24′ thereby allowing the lateralpaddle 24′ to move down and forward along an arcuate path toward thetibial plate 30′ to an anterior and lowered position as shown in FIG.12.

When the lateral paddle 24′ is in the raised position, the lateral inputscrew 34′ is rotated in a second direction in order to move the lateralinterface block 28′ along the lateral input screw 34′ to an anteriorposition as shown in FIG. 13. With the lateral interface block 28′ inthe anterior position, the upwardly-facing ramp surface 138′ of thelateral interface block 28′ engages the downwardly-facing ramp surface134′ of the lateral paddle 24′ thereby lifting the lateral paddle 24′ upand back along an arcuate path from the tibial plate 30′ to a raised andposterior position as suggested by arrow 135′ in FIG. 13.

Turning now to FIG. 14, another driver 14′ configured for use with thejoint distractors 12, 12′ is shown. The driver 14′ includes a handle 50′and a shank 76′ defining a longitudinal axis 61′ of the driver 14′. Thehandle 50′ is coupled to the shank 76′ and provides a structure that ahealthcare provider may grasp during operation. The shank 76′ is formedto include a head 80′ spaced apart from the handle 50′. The head 80′illustratively has a hexagonal shape with six flat sides configured tobe received by the medial or lateral inputs 32, 34 of the jointdistractor 12 or the other medial or lateral inputs 32′, 34′ of theother joint distractor 12′. In other embodiments, the head 80′ may haveany other shape having at least one flat side or another suitable shape.

While the disclosure has been illustrated and described in detail in thedrawings and foregoing description, such an illustration and descriptionis to be considered as exemplary and not restrictive in character, itbeing understood that only illustrative embodiments have been shown anddescribed and that all changes and modifications that come within thespirit of the disclosure are desired to be protected.

The invention claimed is:
 1. An orthopedic surgical instrumentcomprising a joint distractor including a tibial platform, a medialpaddle, and a lateral paddle, each paddle (i) configured to be raisedand lowered relative to the tibial platform independent of the otherpaddle and (ii) having a top surface; and a driver including anelongated body, a user control coupled to the elongated body, a medialoutput shaft connected to and extending out from the elongated body andoperatively coupleable to the medial paddle, and a lateral output shaftconnected to and extending out from the elongated body parallel to themedial output shaft and operatively coupleable to the lateral paddle;wherein (i) the medial output shaft is configured to move the medialpaddle between a raised position and a lowered position relative to thetibial platform in response to operation of the user control, (ii) thelateral output shaft is configured to move the lateral paddle between araised position and a lowered position relative to the tibial platformin response to operation of the user control, and (iii) the top surfacesof the medial paddle and the lateral paddle extend parallel to oneanother when one paddle is in the raised position and the other paddleis in the lowered position.
 2. The orthopedic surgical instrument ofclaim 1, wherein the tibial platform of the joint distractor includes atibial plate, a medial input configured to engage the medial outputshaft of the driver when the driver is coupled to the joint distractor,and a lateral input configured to engage the lateral output shaft of thedriver when the driver is coupled to the joint distractor.
 3. Theorthopedic surgical instrument of claim 2, wherein the joint distractorincludes a medial interface block configured to move between an anteriorposition adjacent to a front panel of the tibial plate when the medialpaddle is in the lowered position and a posterior position adjacent to aback panel of the tibial plate when the medial paddle is in the raisedposition.
 4. The orthopedic surgical instrument of claim 3, wherein themedial interface block is formed to include a threaded hole extendingthrough the medial interface block.
 5. The orthopedic surgicalinstrument of claim 3, wherein the medial paddle includes a ramp surfaceengaging the medial interface block.
 6. The orthopedic surgicalinstrument of claim 5, wherein the ramp surface of the medial paddle isa downwardly-facing ramp surface.
 7. The orthopedic surgical instrumentof claim 5, wherein the joint distractor includes a lateral interfaceblock configured to move between an anterior position adjacent to thefront panel of the tibial plate when the lateral paddle is in thelowered position and a posterior position adjacent to the back panel ofthe tibial plate when the lateral paddle is in the raised position andthe lateral paddle includes a ramp surface engaging the lateralinterface block.
 8. The orthopedic surgical instrument of claim 2,wherein the medial paddle moves between an anterior position when themedial paddle is in the lowered position and a posterior position whenthe medial paddle is in a raised position, and the lateral paddle movesbetween an anterior position when the lateral paddle is in the loweredposition and a posterior position when the lateral paddle is in a raisedposition.
 9. The orthopedic surgical instrument of claim 8, wherein thejoint distractor includes a medial swing arm pivotably coupled to themedial paddle and the tibial plate, and a lateral swing arm pivotablycoupled to the lateral paddle and the tibial plate.
 10. An orthopedicsurgical instrument comprising a joint distractor including (i) a tibialplatform having a tibial plate, (ii) a medial paddle, (iii) a lateralpaddle, (iv) a medial swing arm pivotably coupled to the medial paddleand the tibial plate, and (v) a lateral swing arm pivotably coupled tothe lateral paddle and the tibial plate; and a driver operativelycoupleable to the joint distractor including a user control situated ata first end and an output shaft situated at a second end; wherein thetibial platform includes a medial input configured to be engaged by theoutput shaft of the driver and a lateral input configured to be engagedby the output shaft of the driver; wherein the medial input includes amedial input screw positioned between the tibial late and the medialswing arm, the medial input screw configured to rotate to move themedial paddle between a raised and lowered position; wherein the lateralinput includes a lateral input screw positioned between the tibial plateand the lateral swing arm, the lateral input screw configured to rotateto move the lateral paddle between a raised and lowered position; andwherein each of the medial swing arm and the lateral swing arm isconfigured to move along an arcuate path to guide movement of itscorresponding paddle between a raised position and a lowered positionindependent of the other paddle in response to a user coupling theoutput shaft to one of the inputs and operating the user control torotate the medial input screw and the lateral input screw, each of themedial paddle and the lateral paddle includes a corresponding topsurface, and the top surface of the medial paddle extends parallel tothe top surface of the lateral paddle when one paddle is in the raisedposition and the other paddle is in the lowered position.
 11. Anorthopedic surgical instrument comprising a joint distractor including atibial platform, a medial paddle, and a lateral paddle, each paddle (i)configured to be raised and lowered relative to the tibial platformindependent of the other paddle and (ii) having a top surface; and adriver including an elongated body, a user control coupled to theelongated body, a medial output shaft extending out from the elongatedbody and operatively coupleable to the medial paddle, and a lateraloutput shaft extending out from the elongated body and operativelycoupleable to the lateral paddle; wherein (i) the medial output shaft isconfigured to move the medial paddle between a raised position and alowered position relative to the tibial platform in response tooperation of the user control, (ii) the lateral output shaft isconfigured to move the lateral paddle between a raised position and alowered position relative to the tibial platform in response tooperation of the user control, and (iii) the top surfaces of the medialpaddle and the lateral paddle extend parallel to one another when onepaddle is in the raised position and the other paddle is in the loweredposition; wherein the tibial platform of the joint distractor includes atibial plate, a medial input configured to engage the medial outputshaft of the driver when the driver is coupled to the joint distractor,and a lateral input configured to engage the lateral output shaft of thedriver when the driver is coupled to the joint distractor; and whereinthe medial paddle moves between an anterior position when the medialpaddle is in the lowered position and a posterior position when themedial paddle is in a raised position, and the lateral paddle movesbetween an anterior position when the lateral paddle is in the loweredposition and a posterior position when the lateral paddle is in a raisedposition.
 12. The orthopedic surgical instrument of claim 11, whereinthe joint distractor includes a medial swing arm pivotably coupled tothe medial paddle and the tibial plate, and a lateral swing armpivotably coupled to the lateral paddle and the tibial plate.